We just published a new technical report “An Organization-Level View of the Internet and its Implications (extended)”, available at ftp://ftp.isi.edu/isi-pubs/tr-679.pdf.
From the abstract:
We present a new clustering approach for mapping ASes to organizations, to develop an organization-level view of the Internet’s AS ecosystem. We demonstrate that the choice of clustering method and use of a new (though unconventional) data source in the form of company subsidiary information contained in the U.S. SEC~Form 10-K filings are both essential to get accurate results. Evaluating our mapping and validating it against carefully chosen datasets shows few (less than 10%) false negatives for 90% of organizations and few false positives for 60% of our organizations. We apply our map to show the importance of an organization-level view of the Internet by contrasting it with the commonly-used view that considers only an organization’s “main” AS. We find that this main-AS view sometimes severely underrepresents the influence of an organization in terms of announced addresses, geographic footprint, and peerings at Internet eXchange Points (IXPs). For example, for 20% of our organizations, the main-AS view detects only 10-60% of the cities covered by the corresponding organization-level view.